Bug 1567173 - WR Rawtest comparisons r=gw

Differential Revision: https://phabricator.services.mozilla.com/D38499

--HG--
extra : moz-landing-system : lando

gfx/wr/wrench/src/rawtest.rs

@@ -2,14 +2,15 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use crate::{WindowWrapper, NotifierEvent};
-use crate::blob;
 use euclid::{point2, size2, rect};
 use std::sync::Arc;
 use std::sync::atomic::{AtomicIsize, Ordering};
 use std::sync::mpsc::Receiver;
 use webrender::api::*;
 use webrender::api::units::*;
+use crate::{WindowWrapper, NotifierEvent};
+use crate::blob;
+use crate::reftest::{ReftestImage, ReftestImageComparison};
 use crate::wrench::Wrench;
 
 pub struct RawtestHarness<'a> {
@@ -53,6 +54,41 @@ impl<'a> RawtestHarness<'a> {
         self.wrench.renderer.read_pixels_rgba8(window_rect)
     }
 
+    fn compare_pixels(&self, reference: Vec<u8>, test: Vec<u8>, size: FramebufferIntSize) {
+        let size = DeviceIntSize::new(size.width, size.height);
+        let reference = ReftestImage {
+            data: reference,
+            size,
+        };
+        let test = ReftestImage {
+            data: test,
+            size,
+        };
+
+        match reference.compare(&test) {
+            ReftestImageComparison::Equal => {}
+            ReftestImageComparison::NotEqual { max_difference, count_different } => {
+                let t = "rawtest";
+                println!(
+                    "{} | {} | {}: {}, {}: {}",
+                    "REFTEST TEST-UNEXPECTED-FAIL",
+                    t,
+                    "image comparison, max difference",
+                    max_difference,
+                    "number of differing pixels",
+                    count_different
+                );
+                println!("REFTEST   IMAGE 1 (TEST): {}", test.create_data_uri());
+                println!(
+                    "REFTEST   IMAGE 2 (REFERENCE): {}",
+                    reference.create_data_uri()
+                );
+                println!("REFTEST TEST-END | {}", t);
+                panic!();
+            }
+        }
+    }
+
     fn submit_dl(
         &mut self,
         epoch: &mut Epoch,
@@ -574,7 +610,7 @@ impl<'a> RawtestHarness<'a> {
 
         let pixels = self.render_and_get_pixels(window_rect);
 
-        assert!(pixels == original_pixels);
+        self.compare_pixels(original_pixels, pixels, window_rect.size);
 
         // Leaving a tiled blob image in the resource cache
         // confuses the `test_capture`. TODO: remove this
@@ -667,7 +703,6 @@ impl<'a> RawtestHarness<'a> {
         // use png;
         // png::save_flipped("out1.png", &pixels_first, window_rect.size);
         // png::save_flipped("out2.png", &pixels_second, window_rect.size);
-
         assert!(pixels_first != pixels_second);
 
         // cleanup
@@ -905,8 +940,8 @@ impl<'a> RawtestHarness<'a> {
         self.submit_dl(&mut epoch, layout_size, builder, &txn.resource_updates);
         let pixels_third = self.render_and_get_pixels(window_rect);
 
-        assert!(pixels_first == pixels_second);
         assert!(pixels_first != pixels_third);
+        self.compare_pixels(pixels_first, pixels_second, window_rect.size);
     }
 
     // Ensures that content doing a save-restore produces the same results as not
@@ -1012,7 +1047,7 @@ impl<'a> RawtestHarness<'a> {
         let first = do_test(false);
         let second = do_test(true);
 
-        assert_eq!(first, second);
+        self.compare_pixels(first, second, window_rect.size);
     }
 
     // regression test for #2769
@@ -1141,7 +1176,7 @@ impl<'a> RawtestHarness<'a> {
 
         // 5. render the built frame and compare
         let pixels1 = self.render_and_get_pixels(window_rect);
-        assert!(pixels0 == pixels1);
+        self.compare_pixels(pixels0.clone(), pixels1, window_rect.size);
 
         // 6. rebuild the scene and compare again
         let mut txn = Transaction::new();
@@ -1149,7 +1184,7 @@ impl<'a> RawtestHarness<'a> {
         txn.generate_frame();
         self.wrench.api.send_transaction(captured.document_id, txn);
         let pixels2 = self.render_and_get_pixels(window_rect);
-        assert!(pixels0 == pixels2);
+        self.compare_pixels(pixels0, pixels2, window_rect.size);
     }
 
     fn test_zero_height_window(&mut self) {

gfx/wr/wrench/src/reftest.rs

@@ -114,11 +114,11 @@ impl Display for Reftest {
     }
 }
 
-struct ReftestImage {
-    data: Vec<u8>,
-    size: DeviceIntSize,
+pub struct ReftestImage {
+    pub data: Vec<u8>,
+    pub size: DeviceIntSize,
 }
-enum ReftestImageComparison {
+pub enum ReftestImageComparison {
     Equal,
     NotEqual {
         max_difference: usize,
@@ -127,7 +127,7 @@ enum ReftestImageComparison {
 }
 
 impl ReftestImage {
-    fn compare(&self, other: &ReftestImage) -> ReftestImageComparison {
+    pub fn compare(&self, other: &ReftestImage) -> ReftestImageComparison {
         assert_eq!(self.size, other.size);
         assert_eq!(self.data.len(), other.data.len());
         assert_eq!(self.data.len() % 4, 0);
@@ -158,7 +158,7 @@ impl ReftestImage {
         }
     }
 
-    fn create_data_uri(mut self) -> String {
+    pub fn create_data_uri(mut self) -> String {
         let width = self.size.width;
         let height = self.size.height;